Dry chemical fire extinguishing system



June 26, 1962 K. 'c. SLOUGH 3,040,816

' DRY CHEMICAL FIRE EXTINGUISHING SYSTEM Filed March 30, 1960 4 Sheets-Sheet 1 1 VIII w I 20 '28 f I @F l WHI "W mll l 29 INVENTOR Kenneth C. Slough 2! 20 2/ Fig.3 22 W ATTORNEY June 26, 1962 K. c. SLOUGH 3,040,816

DRY CHEIMICAL FIRE EXTINGUISHING SYSTEM :1 II I E 35 H 5 INVENTOR 9 Kenneth C. Slough BY W ATTORNEY June 26, 1962 K. c. SLOUGH 3,040,816

DRY CHEMICAL FIRE EXTINGUISHING SYSTEM Filed March 30, 1960 4 Sheets-Sheet 3 Fig.8

INVENTOR Kenneth C. Slough ATTORNEY June 26, 1962 K. c. SLOUGH DRY CHEMICAL FIRE EXTINGUISHING SYSTEM Filed March 50, 1960 4 Sheets-Sheet 4 Fig.1:

INVENTOR Kenneth C. Slough ATTORNEY 3,040,816 Patented June 26, 1.962

3,040,816 DRY CHEMICAL FIRE EXTINGUISHING SYSTEM Kenneth C. Slough, Midland, Tex., assignor to Fire Boss, Inc, Fort Worth, Tern, a corporation of Texas Filed- Mar. 30, 1960, Ser. No. 18,590 7 Claims. (Cl. 169-9) This: invention relates to adry chemical fire extinguish ing, system and more particularly to apparatus for extinguishing fires. in which dry powder is, agitated by'mechanical movementv of the powder container and simultaneously aerated bya stream of gas to thoroughly fluidize the powder as it is discharged from the container through a conduit upon afire.

In further particular, the. present invention relates to improvementsin the apparatus disclosed in US. Patent No. 2,923,360, issued February 2, 1960, to. H. T. Porter, for Automatic Inverting and Aerating Pressurized, Dry Chemical Fire-Extinguishing System, assigned to the as signee of the present application. *In the apparatus of the aforementioned patent, a spherical, dry chemical powder container is discharged through flexible conduits attached to a filler cap outside. the periphery of the spherical container. The conduits interfere withv the inversion of the container and vary in internal resistance as they flex when the apparatus is operated. Such flexible conduits have inherently high resistance to fluid flow therethrough and such resistance increases with use. Moreover, the flexible conduits deteriorate relatively rapidly with age and become stifi and likely to crack at low temperatures, thus impairing the reliability of the apparatus.

Also, in the apparatus of the aforementioned patent, the latching arrangement for the dry chemical container is operated independently of the control means for inverting and pressurizing the container; thus, at least two separate operations are required to put the apparatus in action. During the excitement of a tire, the operator may fail to perform one or the other of the required operations with consequent malfunctioning of the unit.

It is, therefore, an object of the present invention to provide a dry chemical fire extinguishing apparatus of I the inverting type in which the initial sections of the line or lines for discharging the dry powder from the container are located inside the container and in which the contents ofthe container is discharged through the shaft on which the container pivots.

Another object of the invention is to eliminate the use of flexible conduits for conducting cfluidi'zed powder-from the container to the hoses or distribution conduits.

Another object of the invention is to provide a discharge system for the dry chemical container having a low internal resistance.

Another object is to simplify operation of the apparatus by combining a plurality of necessary control devices so that they are operated. by a single, simple master control handle.

Still another object is toprovide an apparatus of. the foregoing character in which dry powder cannot contaminate portions of they gas system which must be kept clean.

In general, the dry chemical fire extinguishing, apparatus of the invention includes a normally upright, sealed, pressure resistant container for storing dry chemical fire. extinguishing powder therein, a source of gas under pressure, a gas supply conduit conducting gas from the source tothe interior of the container, the supply conduit terminating in the container adjacent to the top thereof, and a normally closed gas valve in the supply conduit operable to admit gas under pressure from the source to the container. The container, which maybe and preferably is spherical, is mounted forrotation about a horizontal, axis to turn from the upright position to an inverted position. A discharge conduit passes, through the wall of the container coaxially with the axis of rotation of the container, and terminates interiorly of the container adjacent the interior terminal end of the gas sup,- ply conduit. A normally closed discharge valve is providedinthedischarge conduit or the hose leading therefrom operable to discharge the contents of the container upon a fire, and means is provided for rotating the container from the upright position to the inverted position.

The discharge conduit. may include a hollow shaft for rotatably' mounting the container and; an extension pipe within the container communicating with the interior of the shaft, extending upwardly, and terminating in an opening adjacent tov the interior terminal end of the gas supply conduit. A rotary coupling device may connectthe hollow shaft to a relatively fixed section, of the discharge system, such as the hose which conducts the fire extinguishing chemical to be discharged uponv a fire.

Further, in. general, they apparatus of they invention includes a normally closed gas valve in the conduit supply,- ing gas to the interior of the container, a source of power driving a motor for rotating the container together with a motor actuator for applying power to the motor, a releasable latch normally restraining the container in up right position, and a master control operatively associated with the gas valve, the motor actuator, and the latch and operable to substantially simultaneously open the gas valve, operate the actuator and release the latch.

Other aims, objects andadvantages of the invention will be set forth in or apparent from the following detailed description of exemplary apparatus in accordance with the invention, such apparatus being shown in thedrawings, in which:

FIG. 1 is a plan view of a skid-mounted, dry chemical fire extinguishing apparatus embodying the principles of the invention;

FIG. 2 is an elevational view of the apparatus;

FIG. 3 is an end viewof the apparatus;

FIG. 4 is an enlarged plan view of the apparatus with the housing removed; v

FIG. 5 is a sectional: view taken along the line 55 of FIG. 4;

FIG. 6isa sectional view taken along the line 66 of FIG. 5;

'FIG. 7 is a further enlarged, fragmentary, elevational view of the control section of the apparatus;

FIG. 8 is a perspective view of a portion of the control section of FIG. 7;

FIG. 9 is a sectional View taken along the line 9-9 of H6. 5

FIG. 10 is a diagrammatic view of the apparatus; and

FIG. 1 1 is a view of a modified form of dry chemical container and mounting means therefor suitable for use in the apparatus of the invention, parts being broken away to showthe interior of the container.

Referring to the drawings, particularly to FIGS. 1 to- 3, the dry powdered chemical fire extinguishing apparatus shown has a base or skid 20 constructed of channel side members 21 and 22 and tubular end members 23 and 24. The skid supports a spherical container 25, mounted, in a manner that will-be explained hereinafter, for rotation on a horizontal axis. The container is adapted to store therein dry chemical fire extinguishingpowder, such as pulverulent sodium bicarbonate containing a small, percentage of tri-calcium phosphate to enhance flow characteristics of the mixture, the mixture being surface treated with a small percentage of a metallic:v stearate, such as zinc stearate, to render the powder mixture more resistant to absorption of moisture from the air. The container has a hand wheel 26, by which an operator may rotate the container in certain situations to be described hereinafter. An instrument and control panel 27 is located on the side of the apparatus. The container rotates within a sheet metal housing 28 mounted on the skid and surrounding the lower portion of the sphere. A housing section 29 is provided at the other end of the skid and has upper doors 30 and 31 hinged, respectively, at 32 and 33 and secured by trunk latches 34. The doors are raised to give access to the hoses, to be described. The'housing section 29 may be removed from the skid to permit the gas bottles, described hereinafter, to be installed or replaced as required. 1

Turning now to FIGS. 4 to 6, a source of gas under high pressure is provided by a pair of gas cylinders 35, filled with nitrogen or other suitable, preferably inert, gas. The cylinders are supported on transverse V-shaped channel members 36 and secured in place'by a clamping assembly 37. The gas cylinders have the usual outlet valves 38 controlling the flow of nitrogen into the high pressure gas lines 39. s r V The spherical container 25 has a horizontal, diametral shaft40 journalled in pillow block bearings 41 mounted on transverse bearing support members 42 and'42a welded to the channel members 21, 22. The shaft is hollow and extends entirely through the spherical container, being welded to the shell 43 of the container at each side. Interiorly of the container, the shaft is provided with an inverted truss structure 44 to increase the load carrying capacity of the shaft. One end of the shaft is closed by a cap 45. To the other end of the shaft is connected a rotary coupler 46 having a male element 47 threaded to the shaft and a complementary female element 48 threaded to a header pipe 49. The header pipe is mounted in a stationary position on the skid, and the rotary coupler 46 permits the container and shaft to rotate relative to the header pipe while maintaining a fluid-tight connection between the shaft and the header pipe. The header pipe terminates rearwardly in a union 50, to which a conduit (not shown) may be connected'for delivery of fluidized fire extinguishing composition to a remote point when the unit is permanently installed at a selected location. A deluge valve 51 in the header pipe commands flow outwardly of the header pipe. When the unit is employed as a mobile unit, the deluge valve is closed, and fire extinguishing material is delivered to the points of use through hoses 52, 52. The hoses are connected to the header pipe by nipples 53 between the rotary coupler and the, deluge valve. Each hose has a delivery nozzle 54 and a discharge valve 55. When not in use, the hoses are coiled on racks 56 supported on a transverse bridge 57 mounted on the skid. 1 The container shaft 40 communicates with the interior of the container 25 through a pair of extension pipes 58 welded to the hollow shaft and terminating in openings 59 adjacent to the shell 43 on opposite sides of andadjacent to the filler neck 60, which openingsare at the top of the sphere when the latter is in the upright position illustrated in the drawings. The filler neck is closed by a removable cap 60a. The hollow shaft 40 may have a partition 40a which blanks oif the hollow of the shaft to the left of the extension pipes 58 to'keep fire extinguishing chemical from entering this section of the shaft.

' A gas inlet pipe 61 enters the spherical container through the shell, preferably at a location near the axis of the sphere. The gas inlet pipe is welded to the shell where it passes through the latter, and extends upwardly to a point near the filler neck and at one side thereof. The

' inlet pipe has a transverse terminal portion 62 extending horizontally between the pipes 58 and terminating in an opening 63 located between the openings 59 of the extension pipes 58. Gas is supplied to the gas inlet pipe through a flexible conduit 64.

Power for turning the sphere from the illustrated normally upright storage position to the inverted active po- 4. sition is provided by a pneumatic motor 65 of the double acting, piston and cylinder type. As best seen in FIG. 6, the motor has a cylinder 66 mounted on brackets 67 welded to the bearing support member 42. The cylinder is closed at the ends by conventional cylinder heads 68 and 69, the latter having a central opening through which a piston rod 70 extends. Inside the cylinder, the piston rod is secured to a piston 71 slidable in the bore of the cylinder. The usual gas connectors 72 and 73 communicate with the interior of the cylinder at the upper and lower ends thereof, respectively. The outer end of the piston rod carries a rack member 74, formed of a length of sprocket chain welded to the piston rod. The rack engages a sprocket or pinion 75 fixed to the shaft 40, whereby the shaft and container are rotated upon reciprocation of the rack by the motor 65. Gas for operating the motor is supplied through the supply conduits 76 and 77.

Nitrogen from the gas cylinders 35, is used to operate the pneumatic motor 65 for inverting andreinverting the container, and to aerate and fluidize the dry powder in the container 25. Referring to FIGS. 7 and 10, it is seen that the high pressure gas lines 39 leading from the nitrogen cylinders 35 feed into a high pressure main 78 having a main valve 79 therein. A high pressure gauge 80 registers the pressure in the main. The main feeds into a pressure reducing valve 81. Gas under reduced pressure issues from the pressure reducing valve into a low pressure gas line 82 and passes thence through a master control valve 83 into a pipe section 84. A low pressure gauge 85 indicates pressure in this pipe section. From the T 86, the low pressure gas is conducted through the conduit 64 and through a check valve 87 into the gas inlet pipe supplying fluidizing gas to the interior of the spherical container 25. I

From a branch of the T 86, low pressure gas is supplied to operate the pneumatic motor 65 through a branch line 88, which may include a second pressure reducing valve 89 to regulate to the desired degree the pressure of gas supplied to the pneumatic motor. A manually operable motor control valve 90 receives gas from the branch line 88 and selectively distributes it through the motor supply conduits 76 or 77 to the upper or lower end of the motor cylinder 66. The motor control valve 90 has an operating handle 91 normally spring biased to a setting in which gas is suppliedthrough the conduit 77 to the lower end of the cylinder to drive the piston 71 and rod 7 0 upwardly to rotate the spherical container 25 through 180 to the inverted position. above the piston is forced back through the conduit 76 to the motor control valve 90 and is exhausted therethrough to the atmosphere by way of ports 92 in the side of the valve.

When the operating handle is manually pressed against the resilient bias acting thereon to a second setting, and

held in such second setting, the action of the pneumatic motor is reversed. In the second setting of the motor control'valve, gas flows through the supply conduit ,76 to the upper end of the motor cylinder and forces the piston down to reinvert the container. Gas from the lower end of the cylinder returns through the conduit 77 and is exhausted to atmosphere through the side ports 92 of the motor control valve.

The container 25 is normally releasably locked in up- 1 right position by a mechanism which will now be described with reference to FIGS. 7 and 8, to which attention is here directed. A latch plate 93, Welded to the side of the container 25, has a hole 94 therein, loosely receiving alatch pin 95 slidably mounted in bearing blocks 96 and 97 carried by a support frame 98. The latch pin is urged into the hole in the latch plate by a compression spring 99'wrapped loosely about the pin and acting between the bearing block 97 and a collar 100 fixed to the pin by a set screw 101 The latch pin has a yoke 1G2 at one end, the arms 102a and 102b of which embrace an operating cam 103 mounted on a control In this operation, gas

shaft 104. The. shaft is rotatably mounted in bearing blocks. 105i and 106 on an extension 107 of the frame 98, and is. rotated by a master control handle 108, which, as seen in FIG. 2, is positioned in front of the control panel 27 for ready availability to an operator. As seen in FIG. 8, the spring 99 presses the latch pin into the hole of thelatch plate 93. The rise 103a of the cam is seen in FIG. 8 in its lowermost position. \Vhen the master control handle is rocked 90 in the direction of the arrow of FIG. 8, the rise of the cam 193 is rotated counterclockwise to a position pointing to the right as seen in FIG. 8. In moving to this position, the rise of the cam engages the yoke arm 10211 and translates the yoke and latchpin 95 to the right, thereby withdrawing the latch pin from the hole in the latch plate 93 and unlatching the container 25.

The rocking of the master control handle ninety degrees counterclockwise not only effects unlatching of the powder container 25 but also simultaneously effects the opening of the master control valve 83. To this end, the control shaft 164 has an arm- 109 afiixed thereto to the outer end of which is pivoted the upper end of a link 110, the lower end of the link being pivoted to another arm 111 which opens the master control valve when swung through ninety degrees.

As seen in FIGS. 4 and 5, a stop plate 112 is mounted on a. pair of lateral members 113, 113 welded to the channel members 21, 22' of the skid. The plate hasa semicircular recess 114 disposed to receive the filler neck 60 of the powder container when the latter has been rotated through 180 degrees to the inverted position to prevent overrotation of the sphere.

Although the operation of the fire extinguishing unit shown in the drawings will be understood from the foregoing description by persons skilled in the art, a typical mode of operation will be now be described. Referring to, FIG. 10, the container 25, seen in the upright position, is filled with dry chemical fire extinguishing powder by removing the cap 60a and pouring powder through the filler neck 60. The cap is replaced. Discharge valves 55 at the hose nozzles and the deluge valve 51 are closed. The master control handle is moved, if necessary, to the illustrated position to close the master control valve 83 and to latch the container in upright position. The main valve 79 is closed. Fully charged nitrogen cylinders 35 with the valve 38 closed are connected to the high pressure gas lines 39. The motor control valve 9% is checked to insure that it is set in the proper position to effect inversion of the container when motivating gas is supplied through the branch line 88. The apparatus is thus put in standby condition.

To. put the unit in ready condition, the gas cylinder valves. 38 and the main valve 79 are opened.

When it is desired to attack a fire, the hoses 52 are uncoiled each by a. hoseman who takes position near the fire manning the nozzles. An operator at the control panel of the unit swings the master control handle 90 counterclockwise, thus unlatching the sphere and opening the master control valve 83 in a single movement. Gas flows from the high pressure main through the reducing valve 81,. master control valve 83, pipe section 84 and second reducing valve 89 through branch line 88 at a proper pressure to operate the pneumatic, motor 65. This stream of gas is directed by the motor control valve 90. to. the lower end of the pneumatic motor through the supply conduit 77. Entering the lower end. of the motor cylinder, the gas forces the piston upwardly, moving the rack 74 in a direction to rotate the container 25 through. an arc of 180, forwardly and downwardly as seen; in FIG. 10, to a position in which the tiller neck 60 comes to rest against the stop plate 112 shown in FIG. 5.

At the same time, gas from the pipe section 84. flows through the check valve 87, the conduit 64 and the gas 6 inlet pipe 61, and enters'the container at high velocity from the terminal opening 63 of the gas inlet pipe.

Thus, as the sphere is being rotated to inverted position, gas under pressure is introduced at high velocity into the sphere, whereby the powder in, the sphere is mechanically agitated by the rolling action of the sphere and aerated by the swirling gas stream to thoroughly fiuidize the dry powder and render it amenable to how freely from the'container. I

After sphere has reached inverted position, and the low pressure gauge indicates a steady pressure condition, which is ordinarily attained at about the time that the sphere comes to rest in the inverted position, the hosemen are notified; Then, the hosemen open the discharge. valves 55 and the fluidized dry chemical flows through the extension pipes 58, the hollow shaft 40; the header pipe 49 and the hoses/52, to be discharged through the nozzles 54' upon the fire.

When the fire has been extinguished, thedischarge valves 55 are closed. To reinvert the container, the operator at the unit moves the operating handle 91 of the motor control valve 9i? to the setting at which gas is directed from the branch line 8S through the supply conduit 76 to the upper end of the motor cylinder to force the piston therein in a downward direction and to move the rack member in a direction to rotate the container tothe upright position. The operating handle is held in this setting throughout the reinversioncycle. Should the container be partially filled with powder, it may be necessary to manually assist the reinversion of the container, and this is done by means of the hand wheel 26. I

When the container reaches the upright position, the master control handle 1% is returned to the position illustrated in FIG. 10. This action latches the sphere in upright position and closes the master control valve 83. Then, the operating handle of the motor control valve is released" and the spring therein returns it tothe setting for inverting the sphere. The gas still under pressure within the sphere is now employed to blow out the discharge lines by momentarily opening the discharge valves 55, thereby clearing the lines and relieving pressure in the container. The check valve. 8'7 prevents reverse flow through the gas inlet pipe 61 and averts contamination of the motor, gauges, etc., with dry powder.

After use, the main valve 79- and the gas cylinder valves 38. are closed. The unit is then recharged and placed. in standby condition in. preparation. for a subsequent use.

Where the unit is permanently installed and the union 50 is connected to. a permanent dry chemical delivery pipe, the operation is similar to that just described except that the. deluge valve 51 is operated instead of the discharge valves 55 at the nozzles.

An alternative arrangement for discharging the container is shown in FIG. 11, in. which figure parts similar to parts in the apparatus. of FIGS. 1 to; 1 0 are desig nated: by corresponding, but primed, reference numerals. Referring to FIG. 11, there. is shown a container 25' having a diametral shaft 49', journalled in pillow block bearings 41, 41', carried by hearing support members 42., 4221. The shaft has a pinni'on 75 driven by a rack (not shown) for pivoting the container from upright to inverted position. The relatively fixed header pipes 49' and 49a are connected by rotary couplers 46' and 46's: to opposite ends of the. hollow shaft 46 A partition 40'a divides the hollow shaft into two. opposed shaft sections. From the left-hand shaft section, an extension pipe 58 extendsv upwardly to an opening 59' adjacent to and sl-ightly to the left of the filler neck 69. A similar extension pipe 58%; extends from the right-hand section of the shaft upwardly to an opening 59'a located adjacent the shell 43' and slightly to. the right of the filler neck. A gas inlet pipe l'a has an upper transverse terminal portion 62? having an opening. similar to the opening 63 of the gas inlet pipe shown in FIG. 4,

7 V the openings being similarly located. Gas under pressure is admitted to the gas inlet pipe through the conduit 64.' i

Hoses, or other discharge conduits (not shown) are connected to the header pipes 49' and 49'a, and such discharge conduits are provided with appropriate discharge valves (not shown) similar to the discharge valves 55 or deluge valve 51 of the apparatus of FIGS. 1 to 10.

The modified container 25 of FIG. 11 may be substituted in an obvious manner for the container 25 in the apparatus of FIGS. 1 to 10. V

The apparatus of FIG. 11 is operated similarly to the apparatus previously described herein. One or both of the discharge hoses may be operated at a time, and one hose may be cut in or out while the other is operating without substantially changing thefiow through the latter. If desired, the partition 40a may be omitted from the apparatus of FIG. ll to increase somewhat the rate of discharge of the container through a single hose.

. I claim: I

I. In a dry chemical fire extinguishing apparatus: a normally upright, sealed, pressure resistant container for storing dry chemical fire extinguishing powder therein; a source of gas under pressure; gas supply conduit means conducting gas from said source to the interior of said container, said conduit means terminating in said container adjacent the top thereof; normally closed gas valve means in said conduit means operable to admit gas under pressure from said source to said container; a discharge conduit, said conduit including a hollow shaft extending horizontally entirely through said container and afixed to said container and projecting outwardly on both sides thereof to provide a pair of trunnions, and extension conduit means within said container communicating with the interior of said shaft, extending upwardly, and terminating in an opening adjacent to the interior terminal end of said gas supply conduit means; normally closed discharge valve means in said discharge conduit operable to discharge the contents of said container upon a fire; bearings journalling said trunnions and permitting rotation of said container; and means. for rotating said container from said upright position to an inverted position.

2. In a dry chemical fire extinguishing apparatus; a normally upright, sealed, pressure resistant container for storing dry chemicalfire extinguishing powder therein; a source of gas under pressure; gas supply conduit means conducting gas from said source to the interior of said container, said conduit means terminating in said container adjacent the top thereof; normally closed gas valve means in said conduit means operable to admit gas under ressure from said source to said container; a discharge conduit having a fixed section'xexterior to said container, said conduit including a hollow shaft extending horizontally entirely through said container and afiixed to said container and projecting outwardly on both sides thereof to provide a'pair of trunnions, rotary coupling means in said discharge conduit coupling said hollow shaft to said fixed section of said discharge conduit, and extension conduit means within said container communicating with the interior of said shaft, extending upwardly, and terminating in an opening adjacent to the interior terminal end of said gas supply conduit means; normally closed discharge valve means in said discharge conduit operable to discharge the contents of said container upon a fire; bearings journalling said trunnions and permitting rotation of said container; and means for rotating said container from said upright position to an inverted position.

3. In a dry chemical fire extinguishing apparatus; a normally upright, sealed, pressure resistant container for storing dry chemical fire extinguishing powdertherein; a source of gas under pressure; gas supply conduit means conducting gas from said source to the interior of'said container, said conduit means terminating in said container adjacent the top thereof; normally closed gas valve means in said conduit means operable to admit gas under pressure from said source to said container; at .discharge conduit having a fixed section exterior to said container, said conduit including a hollow shaft extending horizontally entirely through said container and afiixed to said container and projecting outwardly on both sides thereof to provide a pair of trunnions, rotary coupling means in said discharge conduit coupling said hollow shaft to said fixed section of said discharge conduit, and a pair of extension conduits within' said container communicating with the interior of said shaft, extending upwardly, and terminating in openings adjacent to and on opposite sides of the interior terminal end of said gas supply conduit means; normally closed discharge valve means in said discharge conduit operable to discharge the contents of said container upon a fire; bearings journalling said trunnions and permittin rotation of said container; and means for rotating said container from said upright position to an inverted position. 7

4. In a dry chemical fire extinguishing apparatus: a normally upright, sealed, pressure resistant container for storing dry chemical fire extinguishing powder therein; a source of gas under pressure; gas supply conduit means conducting gas from said source to the interior of said container, said conduit means terminating in said container adjacent the top thereof; normally closed gas valve means in said conduit means operable to admit gas under pressure from said source to said container; discharge conduit means, said conduit horizontally entirely through said container and afiixed to said container and projecting outwardly on both sides thereof to provide a pair of tlunnions, rotary coupling means coupling each end of said shaft to fixed sections of said discharge conduit means, partition means in the hollow of said shaft Within said container, first extension conduit means within said container communicating with the interior of said shaft on one side of said partition means, extending upwardly, and terminating in an opening adjacent to and at one side of the interior terminal end of said gas supply conduit means, and second extension conduit means within said container communicating with the interior of said shaft on the other side of said partition means, extending upwardly, and terminating in an opening adjacent to and at the other side of the interior terminal end of said gas supply conduit means; normally closed discharge valve means in said discharge conduit operable to discharge the contents of said container upon a fire; bearings journalling said trunnions and permitting rotation of said container; and means for rotating said container from said upright position to an inverted position.

5. In a .dry chemical fire extinguishing apparatus: a

normally upright, sealed, pressure resistant container for storing dry chemical fire extinguishingpowder therein; a source of gas under pressure; gas supply conduit means conducting gas from said source to the interior of said container, normally closed gas valve means in said conduit means operable to admit gas under pressure from said source to said container; means mounting said container for rotation about a horizontal axis to turn from said upright position to an inverted position; a discharge conduit passing through the wall of said container and terminating interiorly of said container adjacent the interior terminal end of said gas supply conduit means; normally closed discharge valvemeans in said discharge conduit operable to discharge the contents of said container upon a fire; a source of power; power driven means operatively connected to said source of power for rotating said container from said upright position to said inverted position; actuating means for applying power from said source to said power driven means for operating the latter; releasable latch means comprising a latch pin received in a hole in a plate on said container normally retaining said container in said upright position, said pin being withdrawable from said hole to release said container for rotation; master control means; and means operatively associating said master control means with said gas valve means, said actuating means and said latch means and operable to substantially simultaneously open said gas valve means, operate said actuating means, and withdraw said pin from said hole to release said latch means.

6. In a dry chemical fire extinguishing apparatus: a normally upright, sealed, pressure resistant container for storing dry chemical fire extinguishing powder therein; a source of gas under pressure; gas supply conduit means conducting gas from said source to the interior of said container, said conduit means terminating in said container adjacent the top thereof; normally closed gas valve means in said conduit means operable to admit gas under pressure from said source to said container; 2. check valve in said gas supply conduit means permitting gas to flow from said source to said container and preventing flow of gas in the opposite direction; means mounting said container for rotation about a horizontal axis to turn from said upright position to an inverted position; a discharge conduit passing through the wall of said container coaxially with the axis of rotation of said container and terminating interiorly of said container adjacent the interior terminal end of said gas supply conduit means; normally closed discharge valve means in said discharge conduit operable to discharge the contents of said container upon a fire; and means for rotating said container from said upright position to said inverted position.

7. In a dry chemical fire extinguishing apparatus: a sealed, pressure resistant, spherical container for storing dry chemical fire extinguishing powder therein; a horizontal shaft extending diametrically through said container, said shaft being afiixed to said container and projecting outwardly on both sides thereof to provide a pair I, of trunnions, said shaft being hollow from an outer end to a location encompassed within said container; extension conduit means Within said container communicating with the interior of said hollow shaft, extending up wardly, and terminating adjacent to the top of said container; a valved discharge conduit coupled to the hollow outer end of said shaft; a source of gas underpressure; gas supply conduit means conducting gas from said source to the interior of said container; normally closed gas valve means in said gas supply conduit means operable to admit gas under pressure from said source to said container; bearings journalling said trunnions and permitting rotation of said container; and means for inverting said container.

References Cited in the file of this patent UNITED STATES PATENTS Porter l. Feb. 2, 1960 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,040,816 June 26, 1962 Kenneth C. Slough It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 5, line 46, for "valve" read valves column 6, line 10, before "sphere" insert the column 8, line 29, after "conduit", second occurrence, insert means including a hollow s haft extending Signed and sealed this 16th day of October 1962.

(SEAL) Attest:

ERNEST w. SWIDER AVID L- LADD Attesting Officer Commissioner of Patents 

1. IN A DRY CHEMICAL FIRE EXTINGISHING APPARATUS: A NORMALLY UPRIGHT, SEALED, PRESSURE RESISTANT CONTAINERS FOR STORING DRY CHEMICAL FIRE EXTINGUSHING POWER THEREIN; A SOURCE OF GAS UNDER PRESSURE; GAS SUPPLY CONDUIT MEANS CONDUCTING GAS FROM SAID SOURCE TO THE INTERIOR OF SAID CONTAINER, SAID CONDUIT MEANS TERMINATING IN SAID CONTAINER, ADJACENT THE TOP THEREOF; NORMALLY CLOSED GAS VALVE MEANS IN SAID CONDUIT MEANS OPERABLE TO ADMIT GAS UNDER PRESSURE FROM SAID SOURCE TO SAID CONTAINER; A DISCHARGE CONDUIT, SAID CONDUIT INCLUDING A HOLLOW SHAFT EXTENDING HORIZONTALLY ENTIRELY THROUGH SAID CONTAINER AND AFFIXED TO SAID CONTAINER AND PROJECTING OUTWARDLY ON BOTH SODES THEREOF TO PROVIDE A PAIR OF TRUNINIONS, AND EXTENSION CONDUIT MEANS WITHIN SAID CONTAINER COMMUNICATION WITH 